Alzheimer's Disease is a neurodegenerative disease which causes dementia. The period from first detection of AD to termination can range from a few years to 15 years, during which time the patient progressively suffers loss of both mental function and control of bodily functions. There is significant variability in the progress of the disease. While the majority of patients have a gradual, inexorable progression (losing on average 3 to 4 points on the 30 point Folstein mini-mental state score annually), approximately 30% of AD cases have a prolonged stable initial plateau phase lasting several years (Haxby et al., 1992). A subgroup of patients has a fulminant, rapidly progressive downhill course over several years (Mann et al., 1992). Other patients (about 10% of cohorts) remain slowly progressive, showing only gradual decline from year to year (Grossi et al., 1988). The pathological, chemical, and molecular bases of this heterogeneity remain undetermined. Recognition of the variability of AD progression represents an important clinical insight, and may explain the diagnostic difficulties presented by "atypical" cases.
Attempts at predicting the onset of AD or monitoring its progression have met with limited success. While in certain cases, there is a familial manifestation of the disease, it appears that the majority of AD cases are non-familial, and no simple genetic marker for the disease has yet been determined. Much research has focused on the protein beta-amyloid, deposits of which are found in the brains of AD victims.
Methods of predicting, diagnosing in its very early stage, and prognosticating AD and other dementing diseases are needed.